1. Field of the Invention
The present invention relates to a measuring apparatus and a measuring method for measuring a characteristic of a transfer circuit including an optical transmission system, and a transfer circuit that can measure a characteristic easily.
2. Description of Related Art
Conventionally, a transfer circuit including an optical transmission system is known as a transmission system of a signal from a transmitting side device to a receiving side device. For example, the transfer circuit includes a system for transmitting an electrical signal, a system for converting an electric signal into an optical signal, a system for transmitting an optical signal, and a system for converting an optical signal into an electrical signal.
According to a conventional measuring method, in order to diagnose whether the transfer circuit can transmit data rightly, the transfer circuit is diagnosed by generating known pattern data from the transmitting side device and comparing the known pattern data with pattern data received by the receiving side device.
In addition, it is important as a characteristic of a transfer circuit whether a signal transmitted by the transfer circuit can rightly receive by the receiving side device by having a timing margin to some degree. However, the transfer circuit including an optical transmission system has the variation of characteristics of a device such as a light-emitting element and a photo detector and the variation of transmission characteristics by contamination of a plane of light emission and a plane of light incidence.
For this reason, it is preferable to perform detailed measurement including a light receiving characteristic or the like in an optical transmission system. However, it was difficult to perform detailed measurement in a conventional manner.
Therefore, it is an object of the present invention to provide a measuring apparatus, a transfer circuit, and a measuring method that can solve the foregoing problems. The above and other objects can be achieved by combinations described in the independent claims. The dependent claims define further advantageous and exemplary combinations of the present invention.